You can sign up to the event here: 

It is available for free viewing for 1 time only. After that, you will be automatically locked out of the viewing and you will need to purchase the Premium Pass for Lifetime Access. 

We do this because it takes a huge amount of time and $xxx,xxx's to produce these events. We wish we could make it free viewing forever but we need to sell a Premium Pass so we can break even and create more events in future. Unfortunately we don't have a marketing budget like big Pharma :-(